Détails:The captain was cleared for an RNAV runway 05 approach, but the runway lights were not on as the aircraft broke through clouds at 1000 feet, 1 mile from the airport. The aircraft then circled for another approach, but came in high and fast. The 1st officer recommended a go-around, but the captain decided to continue. The aircraft had touched down long and was about to overrun the runway, when the captain retracted the landing gear. The plane then slid off the end of the runway and went over an embankment, becoming airborne for about 140 feet and impacted a large ravine area.The landing weight was estimated to be 14,668 lb where the max. gross weight limit is 14,500 lb.